How does highly pathogenic avian influenza (bird flu) H5N1, become airborne? Ron Fouchier and his team of virologists from Erasmus MC, in Rotterdam, set out to answer that very question. Along the way however, they would face full-scale censorship attempts and fuel worldwide regulation debates that developed into a two-month suspension on influenza research. Why such a reaction? Because they did it, they made bird flu airborne, proving that it could potentially pose a pandemic threat and then published it for the whole world to see.
The group changed the DNA code of H5N1 so that it bared similarities to previous airborne human flu pandemics. This mutant H5N1 virus was injected intranasally (up the nasal passage) to a group of ferrets. Ferrets? Yes ferrets, the group chose ferrets in their studies as they share many similarities to humans in terms of their respiratory system and how they respond to influenza viruses. Through natural selection, the virus was allowed to adapt to the animal through a process known as virus passaging. Here, ferret number one, whose been injected with the virus, has its lungs and specific nasal bones homogenized (so the consistency is the same throughout) and injected intranasally into ferret number two. This process was repeated ten times, before these ‘passage-10 ferrets’ had DNA from their nasal swabs analysed to reveal the genetic makeup of the resulting virus mixture. With a potentially airborne virus produced, the next step was to determine whether the viral mixture was indeed airborne transmissible. To test this, the scientists set up an experiment; healthy ferrets were placed in cages near to ferrets injected with the virus mixture. Nasal and throat swabs from the ‘healthy’ ferrets confirmed successful bird flu transmission.
Bird flu has been responsible for the deaths of tens of millions of birds worldwide, and to-date taken 359 human lives too. Changes to the DNA can lead to changes to the amino-acid composition of the virus, which can compromise their function. The results of this study suggest that as little as five amino acid substitutions are enough to produce a virus that can become airborne in mammals.
Great work, right? Time to publish the results. Not everybody agreed. The group faced hours of interrogation by the National Science Advisory Board for Biosecurity (NSABB), who didn’t want the results published. The censorship attempts were primarily in the interest of preventing serious bioterrorism threats, or misuse of their methods by ‘rogue’ countries, careless or DIY scientists. The group fought and presented their motives clearly; it was in the interest of public health, and preventing or in fact limiting the impact if prevention fails, of a human pandemic threat of H5N1 virus. And as such all findings, including full methodology disclosure should be included. The paper was finally published in Science in June 2012.
In a recent ‘Science and Censorship’ lecture at the University of Cambridge, UK, Fouchier stated that ‘science should never be censored’. He believes that scientists working on projects such as the H5N1 airborne one, all follow a code of conduct. And much of the rules and regulations while in place to prevent misconduct, do nothing to prevent ‘bad guys from doing what they’re already going to do. All they do is slow down the good guys’.